AB0872 RELAPSES OF 129 PATIENTS WITH IDIOPATHIC INFLAMMATORY MYOPATHIES
Authors: J. Choi, J. Kim, B. Ghang, B. Yoo
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> A high dose of glucocorticoid is suggested as initial management of Idiopathic inflammatory myopathies(IIMs), and immunosuppressive agents are added in severe cases [1]. However, since the diseases are rarely diagnosed, few studies have addressed the issue regarding the use of immunosuppressive agents with limited evidence [2]. The treatment of IIMs largely relies on empirical evidence and small studies [3]. As a results, The immunosuppressives have been indeed administered at the discretion of the physicians in practice. The initial glucocorticoid treatment usually leads to a stable phase for IIMs where clinical symptoms are improved, and glucocorticoids are tapered to low doses. A relapse is occasionally observed in clinical practice as the recurrence of muscle or cutaneous manifestations during and after glucocorticoids tapering, although there is no consensus on the definition regarding the relapse of IIMs [4]. Therefore, it is poorly understood which factors are essential to predicting the relapse of IIMs. <h3>Objectives</h3> Few studies have assessed risks for the relapse of idiopathic inflammatory myopathies (IIMs). We investigated relapse in patients with IIMs. <h3>Methods</h3> Patients who were newly diagnosed with IIMs and underwent muscle biopsy between 2000 and 2017 were retrospectively reviewed. The relapse of IIMs was defined as the recurrence of muscle or cutaneous manifestations after reaching the stable phase, leading to ≥50 % increase in the glucocorticoid dosage. The factors associated with the relapse of IIMs were investigated by Cox proportional hazards analysis. <h3>Results</h3> Of the 105 patients with IIMs, relapse was observed in 65 patients (62%). The titer of an antinuclear antibody (ANA) was higher in the relapse group than in the non-relapse group (<i>P</i> = 0.033). In multivariable analysis, three factors were associated with the relapse of IIMs: histopathologic features consistent with IIMs (model 1; HR, 1.69; 95% CI, 1.01-2.83, <i>P</i> = 0.0453) and the use of immunosuppressants before relapse (model 2; HR, 0.50; 95% CI, 0.29-0.86, <i>P</i> = 0.0132). Doubling of ANA titer showed a trend toward an association with relapse albeit without statistical significance (model 1; HR, 1.13; 95% CI, 1.00-1.27, <i>P</i> = 0.0517). <h3>Conclusion</h3> The use of immunosuppressants during a period of tapering glucocorticoid in the initial treatment would help reduce the risk of relapse of IIMs. <h3>References</h3> [1]Meyer A, Scirè CA, Talarico R, Alexander T, Amoura Z, Avcin T, et al. Idiopathic inflammatory myopathies: state of the art on clinical practice guidelines. RMD open. 2019;4(Suppl 1):e000784. [2]Ruperto N, Pistorio A, Oliveira S, Zulian F, Cuttica R, Ravelli A, et al. Prednisone versus prednisone plus ciclosporin versus prednisone plus methotrexate in new-onset juvenile dermatomyositis: a randomised trial. The Lancet. 2016;387(10019):671-8. [3]Sunderkötter C, Nast A, Worm M, Dengler R, Dörner T, Ganter H, et al. Guidelines on dermatomyositis–excerpt from the interdisciplinary S2k guidelines on myositis syndromes by the German Society of Neurology. JDDG: Journal der Deutschen Dermatologischen Gesellschaft. 2016;14(3):321-38. [4]Ponyi A, Constantin T, Balogh Z, Szalai Z, Borgulya G, Molnár K, et al. Disease course, frequency of relapses and survival of 73 patients with juvenile or adult dermatomyositis. Clinical and experimental rheumatology. 2005;23(1):50-6. <h3>Acknowledgements:</h3> NIL. <h3>Disclosure of Interests</h3> None Declared.